Vacuum tube



May 13, 1930. o, w, PIKE 1,758,803

VACUUM TUBE Filed March 14, 1927 i" -i Q! ggg if i Inventor: Otis W. Pi ke 9 His Attorney.

Patented May 13, 1930 QFFICE OTIS W. PIKE, OF SCHENEGTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK VACUUM TUBE Application filed. March 14, 1927. Serial No. 175,056.

The present invention relates to vacuum tubes and more particularly to an arrangement for supporting electrodes in spaced relation in such tubes.

It is one of the objects of my invention to provide a simple and eiiective arrangement whereby four electrodes may be rigidly supported in an evacuated container.

The novel features which I believe to be characteristic of my invention are set forth with particularity in the appended claims. My invention itself. however, will best be understood from reference to the following specification when considered in connection with the accompanying drawing in which the single figure is a perspective view, partly broken away, of a vacuum tube which embodies the features of my invention.

Referring more particularly to the drawing, 1 have indicated at 1 a vacuum tube or electron discharge device of about 50 watt capacity, which is adapted for use in connection with short wave transmission. The tube comprises an evacuated glass container 2 having a pair of oppositely disposed reentrant portions provided with stems 3 and 4 respectively, and a second pair of reentrant portions provided with stems 5 and 5 respectively arranged at an angle of 90 t the stems 3 and 4.

A cathode or filamentary mounted on stem 3 and connected to a pair of leading-in wires 7. A control grid electrode 8 which comprises a coiled wire is mounted directly on a pair of leading-in wires 9 and 10 which extend through stem 4. A pair of oppositely disposed rods 11 and 12 a re welded to the difierent turns of the grid electrode in order to maintain the turns in position and to provide a desired degree of rigidity to the grid.

A. screen or shielding grid 13 surrounds filament 6 and grid electrode 8 and is provided at its opposite ends with collars, one of which let is rigidly mounted on stem 3 and the other of which 15 is slidably mounted on stem 4. Grid 13 extends substantially the entire distance between stems 3 and 4: and provides an effective shield not only between the anode and other electrodes but between however, is obtained'by mounting a pair of electrode 6 is the anode and the leading-in wires connected to the control grid 8 and cathode 3.

Anode 16 comprises a cylindrical body having a plurality of radial flanges 17. The anode is constructed from a plurality of channel sections 18 secured together by punching through the adjacent flanged portions of the channel sections and securing the parts together by metal from the punched portions. The flanges 17 provide the anode with a relatively large radiating surface which is desirable in tubes of this type. A pair of spaced, substantially parallel, leading-in wires 20 and 21 extend through stem 5 and between two adjacent flanges of channels 18 5 thereby providing the anode with a rigid support. By supporting both the grid and the anode directly on a pair of leading-in wires, an increased-high frequency current capacity may be obtained over that which could be obtained by using one large lead-in wire for each electrode. A further advantage is also obtained in the elimination of the usual welds between the leading-in conductors and the electrode supports. To provide the anode with additional rigidity a plurality of wire braces 22 may be applied between flanges 17 and riveted thereto. A more desirable construction,

short, still wires 23 in stem 5'. These wires extend part way into a pair of slots 24 formed in the flanged portion of the anode 16 and permit slight movement of the anode in the direction of stem 5, but hold it rigidly against any lateral movement or vibration.

If desired, a small portion of getter material may be supported from one of the leading-in wires attached to the anode as indicated at 25.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. An electron discharge device comprising a container having oppositely disposed reentrant portions provided with stems, a V reentrant portion positioned at an angle with respect to said stems, a filamentary electrode supported from one of said stems, a grid supported by the other stem, a shielding electrode surrounding said filamentary electrode and grid and supported by one of said reentrant portions, said shielding electrode extending substantially the entire distance between said stems and an anode surrounding 5 said shielding electrode and supported from said angularly-positioned reentrant portion.

2. An electron discharge device comprising a container having oppositely disposed reentrant portions provided with stems, a reentrant portion positioned at an angle with respect to said stems, a filamentary electrode supported from one stem, a grid electrode supported by the other stem, a second grid electrode supported from both of said reentrant portions, and an anode surroundin said second grid electrode and supported from said angularly-positioned reentrant portion.

3. An electron discharge device comprising a container having oppositely disposed reentrant portions provided with stems, a reentrant portion positioned at an angle with respect to said stems, a filamentary electrode supported from one stem, a grid electrode supported from the other stem, a screening electrode supported from one of said reentrant portions and extending a substantial distance beyond both ends of said grid electrode, and an anode surrounding said screening electrode and supported from said angularly-positioned reentrant portion.

In witness whereof, I have hereunto set my hand this 11th day of March, 1927.

OTIS W. PIKE. 36 

